Cash for Clunk­ers boost­ed auto sales by 690,114 units, accord­ing to gov­ern­ment num­bers. Sales for July rose to an annu­al rate of 11.2 mil­lion, but experts wor­ry about a sales bub­ble. Gov­ern­ment offi­cials praised the pro­gram, which cost tax­pay­ers $2.88 bil­lion. Hon­da, Toy­ota and Nis­san account­ed for 41% of the sales.